Philosophy Lesson 12 Descartes' Skepticism

Another inspiration of Descartes' philosophy: skepticism.

I don't know what is true, so I can doubt everything-the root of skepticism.

In the 16 and 17 centuries, people found that tradition and authority were unreliable. There is no America in the Bible. Astronomical geography proves that the earth is not the center of the universe. This is an era when the world outlook falls apart. People want to find a truth to explain the world, but they don't have the ability and can't trust the previous authority. Then what should we believe? Humans began to look for new theories to choose to believe. At this time, Descartes put forward the view that he did not believe in authority, past traditions and everything. Because I don't know what to believe, everything can be doubted.

We can believe that the objective world exists, or we can doubt that we are fish living in a goldfish bowl. The world we see is distorted and not real. We can even think that we are living in a dream and everything is dreaming. Our senses can be manipulated, and we can't know whether we are living in hallucinations. Just like when we read martial arts novels, it is easy to substitute ourselves into the hero. He has the greatest martial arts and enjoys it. That kind of pleasure is an important reason to encourage us to continue reading. Our brains are easily deceived. But the foundation of all thoughts must have its real core, including complete skepticism.

Everything can be doubted, but there is no doubt that I am doubting. No matter what I doubt, I can't deny that I doubt the existence of this objective fact. This is the only thing Descartes found that is practical and can stand any test. I am doubtful about that.

The subject of my doubt is me, and I doubt it too. Descartes said the famous and important famous saying in the history of philosophy: I think, therefore I am. Doubt is a kind of thinking, so I think there must be. Descartes, who sorted out a whole set of philosophical systems after ancient Greece, is called the father of modern philosophy.

The arguments and doubts between monism and dualism have opened people's eyes, but this does not mean that he put forward the correct answer, but leads us to keep thinking and deepen our understanding of the answer and the universe hundreds of years after him.

Descartes put forward skepticism, but his answer is limited, and his cognition and ability only allow him to answer some questions. As I think, so I'm here, and then I don't think. Am I not here? He released the monster of skepticism from the cage, but he couldn't put it back. After so many years of development, our understanding of skepticism has been very profound. There are two main skepticism systems. Now we will pay attention to one of them, the torture of the senses: parallel skepticism.

Torture and doubt the senses. What is the crux of parallel skepticism?

Descartes thinks that I doubt my knowledge because the way to acquire it is unreliable. We know the outside world through our own sensory system. We have five basic senses: eyes, ears, nose, tongue and body, which correspond to color, sound, smell, taste and touch respectively. Are our senses reliable? No. Is what we saw true? Not necessarily. Senses are the reaction of the brain, just like when I was sleeping in bed, I vaguely saw the basketball fly over and subconsciously caught the ball, but I hit the wall and woke up in pain, and found it was an illusion and a dream. We run and fly in our dreams, but really? Obviously not, dreams are just images presented by stimulating the occipital lobe during sleep, not real.

All five of our senses produce hallucinations. Seeing ghosts may be just a problem with the brain nerves and obstacles in the transmission of visual information, but it is real to the experiencer.

More common than auditory hallucination is auditory hallucination. You must have heard voices. When you are waiting for an important notice, when you are absorbed in your mobile phone, you will have auditory hallucinations because you urgently need the phone to ring. The senses are hallucinating. How can we believe them?

Senses are almost the only tool for us to know the outside world. Nothing can transcend the senses. If you deny the senses, you deny everything. This view cannot be refuted at all. This is called complete idealism, and it is serious idealism. Everything is my senses, not everything is my heart. There is no way to prove that there is something outside the heart, not nothing outside the heart. We can't prove that anything we hear or touch is true.

Seeing this, it is estimated that someone jumped up and said, isn't this bullshit? I punched the wall and my hand obviously hurt. Is this fake, too? Yes, it may be false, because touch and pain are feelings. Can you prove anything but feelings?

This is complete disobedience, unbreakable and irrefutable. Idealism is that you can't prove anything other than your heart, because all your measurements are your senses. Although we can fight back, we can only fight back to some extent. We can't deny it, but we can ignore it.

Neglect is not unreasonable, but based on the high consistency and stability of the world around us. If today's moon is made of stone, tomorrow's moon is made of gold and the day after tomorrow's moon is made of cake, then of course we can think that we are living in a dreamland, but this is not the case.

All sciences have found that the world we live in has quite stable logic. It is precisely because of the high stability and consistency of the external world that it is completely meaningless for us to question whether the external world is an illusion. We can describe the world according to stability and consistency and make predictions. We don't need the extra condition of dreamland at all, so we should ignore it.

We have no reason to believe that the external world exists reasonably, but we have no choice but to think that it exists. Hume

Absolute materialism cannot refute absolute idealism, but it can be ignored. This is not to avoid the problem, but to ignore it reasonably. This is the famous Occam razor principle, scraping unnecessary assumptions from the theory and leaving the simplest explanation. Do not add entities unless necessary. I know I can't prove that there is something outside my heart, but I can be careful to think that there is something outside my heart. I can think that everything outside my heart exists. The outside world is completely consistent. You can see, hear and predict, but you can't falsify. So we can believe that we are not dreaming until the evidence that we are surrounded by hallucinations comes out.

Sensory torture and the power of absolute idealism have been said, and the way to crack idealism has also been said, but is this complete sensory skepticism? No, there is another level.

We can believe that what we see is true, but is it really the thing itself? Is this a fact? What you see is not the truth. Just like a little red flower, is the little red flower we see the flower itself? Under the present scientific conditions, we can categorically say no, we have seen it with our eyes, but our eyes can only see things in visible light waves (380 ~ 780 nanometers), but we can't see infrared rays and ultraviolet rays outside visible light waves. Will that little red flower shine? No, red is an attribute of light. The range of visible light waves is the strongest range of solar radiation, and the eyes have the ability to detect the strongest solar radiation. Small red flowers don't shine, but their color comes from the reflection of sunlight. No matter what color the little red flower itself is, it must not be red, and red is excluded. What we see is not the color of the little red flower itself, but the light.

Not only the eyes, but also other organs. Ears can only hear air vibration between16 and 20000 Hz; The tongue can only distinguish four basic tastes: sweet, sour, bitter and salty. Spicy is not the basic taste, spicy is taste bud pain. Our feelings are limited, so is our understanding of noumenon.

We thought we touched the table, but we didn't. That's just the tactile sensation obtained by the reaction of electronic repulsion to nerves. We can never touch the main body of the table. There is a membrane between us and our bodies.

We can only understand a small phenomenon world with limited senses, and we can't touch the ontology of this world. -Kant

The little red flower is an atom, but we can't see it. There is no color, what we see is color. Ontology is an atom, but we can't see the atom. This is a huge gap. There is an insurmountable gap between our feelings and the world around us. The little red flower is just a psychological image constructed by our brain according to our perception. It is abstract and a concept in our minds. We can only think that what we see is a small red flower, which is limited by natural talent. Our innate talent and sensory defects prevent us from touching the truth of things, and the form we see is not true.

So what is the real world like? Sorry, we don't know much about it, and we don't know enough about it. But don't be sad, we have a solution, or Occam razor principle. The psychological image produced by our perception of the outside world is like a map, and the criterion for measuring a map is whether it can take us to our destination. If you can predict and explain according to this map, and you can reach your destination according to this map, it doesn't matter whether the map is the real world or not. We can live according to mental images, regardless of the real face of the world.

That's enough for evolution. Evolution does not let us see the real world, but let us survive. Only with the powerful function of doubt can we realize that evolution has not given us the ability to understand the world. But through skepticism, we began to use science to get close to the real world.

The real world exists, but we have not solved the mystery yet.

In the next section, we will discuss another general direction of skepticism.